Extech Instruments SL250W User manual

User Manual
SL250W Sound Meter
Bluetooth® Connectivity with the ExView® Mobile App

Table of contents
1 Introduction........................................................................1
2 Safety ................................................................................2
3 FCC Compliance .................................................................3
4 Product Description ............................................................4
4.1 Meter Description .......................................................4
4.2 Function Buttons ........................................................ 4
4.3 Display Symbols.........................................................5
5 Operation...........................................................................6
5.1 Powering the Meter ..................................................... 6
5.2 Auto Power Off (APO)..................................................6
5.3 Taking Measurements .................................................6
5.4 Fast/Slow Response ................................................... 7
5.5 Data Hold Function .....................................................7
5.6 LCD Backlight............................................................ 7
5.7 MAX/MIN Readings .................................................... 7
5.8 Bluetooth Operation ....................................................7
6 Maintenance.......................................................................8
6.1 General Cleaning .......................................................8
6.2 Battery Replacement...................................................8
7 Specifications.....................................................................9
7.1 General Specifications................................................. 9
7.2 Measurement Specifications .........................................9
7.3 Environmental Specifications ........................................ 9
7.4 Connectivity Specifications ......................................... 10
8 Two-year Warranty............................................................. 11
8.1 Calibration and Repair Services................................... 11
8.2 Contact Customer Support ......................................... 11
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Introduction
1
Thank you for selecting the Extech SL250W Sound Meter. This meter meas-
ures sound level with its built-in microphone, situated at the top of the meter.
Sound level measurements are shown on the backlit LCD in decibel (dBa)
units.
The meter includes Bluetooth connectivity, MAX/MIN memory, selectable
Fast/Slow response, auto power off, data hold, backlit LCD, and tripod mount.
Using the Extech ExView mobile app, you can pair your smart devices with
the meter using Bluetooth. The app and the W Series meters were developed
together for seamless integration. Download the free app from the App Store
(iOS®) or from Google Play (Android™).
This quality instrument is designed to provide years of reliable service, high
accuracy and simple operation. Please visit the Extech website for additional
information and world-class support.
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Safety
2
Please read all safety information before using this device
CAUTION
• Check for damage to the device’s housing, sensor, display, and battery compartment
before use. If obvious damage or abnormalities are noticed, please discontinue use
and return the device for service.
• Do not attempt to open the meter housing or access the sensor module. There are no
user-serviceable components in this device.
• Replace the batteries immediately after the low battery symbol appears. If the device is
to be stored for a period of months, please remove the batteries and store separately.
• Do not store the device in high temperature or humidity environments, in flammable or
combustible areas, or where a strong electromagnetic field is present.
• This device is designed and produced following the strict requirements of SJ/T 10423
General Specification for Sound Level Meters.
• This device is CE certified.
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FCC Compliance
3
This equipment has been tested and found to comply with the limits for a
Class B digital device, pursuant to part 15 of the FCC Rules. These limits are
designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with the instruc-
tions, may cause harmful interference to radio communications. However,
there is no guarantee that interference will not occur in a particular installation.
If this equipment does cause harmful interference to radio or television recep-
tion, which can be determined by turning the equipment off and on, the user is
encouraged to try to correct the interference by one or more of the following
measures:
1. Reorient or relocate the receiving antenna.
2. Increase the separation between the equipment and receiver.
3. Connect the equipment into an outlet on a circuit different from that to
which the receiver is connected.
4. Consult the dealer or an experienced radio/TV technician for help.
WARNING
Changes or modifications not expressly approved by the party responsible for compliance
could void the user's authority to operate the equipment.
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Product Description
4
4.1 Meter Description
1. Microphone with wind screen attached
2. Backlit LCD (detailed below)
3. Function buttons (detailed below)
4. Tripod mount
5. Battery compartment
4.2 Function Buttons
Power / Bluetooth button
Long press to switch the device on. Short press to switch off.
With the meter powered, long press to switch Bluetooth on/off.
Short press to switch the meter off directly from the Bluetooth mode.
MAX/MIN button
Short press to cycle through MAX/MIN readings. The memories are
cleared each time meter power is cycled.
Data Hold / Backlight button
Short press to freeze/unfreeze the displayed reading. HOLD will display
when data hold is active.
Long press to switch the LCD backlight on/off.
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Product Description
4
FAST / SLOW button
Short press to toggle the Fast and Slow modes. In Fast mode (125 ms)
sounds that peak very quickly, such as a firework ignition or a rifle dis-
charge, can be captured. Slow mode (1 second) is intended for sounds
that are continuous, such as the drone of machinery.
APO ON/OFF With the meter on, long press the power and Hbuttons to switch APO
on/off. The APO symbol is displayed when APO is enabled. APO is
reset each time the meter power is cycled.
4.3 Display Symbols
1. Bluetooth active
2. A-weighted (dBa) sound level reading
3. Maximum reading
4. Minimum reading
5. Data Hold mode
6. Battery status icon
7. Slow response mode
8. Fast response mode
9. Auto Power Off (APO) symbol
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Operation
5
5.1 Powering the Meter
The meter operates on three (3) 1.5 V (AAA) batteries, installed in the rear
compartment.
Long press the power button to switch the meter on. Short press the power
button to switch the meter off. If the meter does not switch on, check the bat-
teries for proper orientation.
When the battery icon appears on the display, replace the batteries immedi-
ately to ensure accurate readings.
5.2 Auto Power Off (APO)
The meter switches OFF automatically five (5) minutes after the last button
press.
The default mode for APO is ON (the APO symbol on the display indicates
that APO is enabled).
To switch the APO function off, with the meter switched on, long press the
power and Hbuttons. The APO symbol will switch off, indicating that the
function is disabled. APO is reset each time the meter’s power is cycled.
Repeat this process to switch APO back on manually.
5.3 Taking Measurements
1. Long press the power button to switch the meter on.
2. Hold the meter in hand, set it on a desk or table, or mount it on a tripod in
the area under test.
3. Read the sound level measurement on the LCD. Sound level measure-
ments are presented in A-weighted decibel units. A-weighted measure-
ments simulate the response curve of the human ear to sound.
4. If the measurement is over range, OL will appear on the display in place of
a typical reading. If the measurement is under range, UN will appear.
CAUTION
Do not touch or otherwise obstruct the microphone.
Do not allow liquids to come in contact with the microphone.
Do not allow dust or other particles to enter the microphone.
Use the windscreen to cover the microphone in windy environments.
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Operation
5
5.4 Fast/Slow Response
Short press the Fast/Slow button to toggle the meter’s response time. Use the
Fast response mode (125 ms) to capture sounds that peak very quickly such
as fireworks. Use the Slow response mode (1 second) to monitor consistent
sounds such as the hum, or drone, of machinery.
5.5 Data Hold Function
Short press the Data Hold (H) button to freeze/unfreeze the displayed read-
ings. While Data Hold is active, HOLD will appear on the LCD.
5.6 LCD Backlight
Long press the backlight button to switch the display backlight on or off.
Excessive use of the backlight will shorten battery life.
5.7 MAX/MIN Readings
When the device is switched on, it begins tracking the highest (MAX) and low-
est (MIN) readings.
Short press the MAX/MIN button to step through the MAX/MIN memories.
The memories are cleared each time the meter power is cycled.
Press the MAX/MIN button again to exit this mode (MAX and MIN symbols
switch off when you exit).
5.8 Bluetooth Operation
Long press the Bluetooth button with the meter on, to switch Bluetooth on
or off. This communication symbol is shown when Bluetooth is on.
The Bluetooth utility allows you to remotely monitor readings on an iOS or An-
droid smart device using the Extech ExView mobile app designed for use with
this meter.
Download the ExView mobile app from the App Store for iOS devices or from
Google Play for Android devices. Instructions for mobile app use are available
from the ExView product page on the Extech website (link below).
http://www.extech.com
Switch APO off when using Bluetooth by pressing and holding the power
and Hbuttons for 2 seconds (the APO symbol will switch off). This will pre-
vent the meter from automatically switching off while you are logging data or
monitoring readings in real time on your smart device.
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Maintenance
6
CAUTION
Warning: Do not open the housing or microphone module. Service should only be per-
formed by factory personnel, there are no user-serviceable components in this device.
6.1 General Cleaning
Wipe the housing with a damp cloth as necessary to clean. Do not use abra-
sives or solvents to clean this device. Do not allow moisture to enter the mi-
crophone or the meter housing.
6.2 Battery Replacement
This device is powered by three (3) 1.5 V (AAA) batteries. When the low bat-
tery symbol appears, replace the batteries immediately, as explained below.
1. Switch the meter off and remove the rear battery compartment cover.
2. Replace the batteries, observing correct polarity. Always use batteries of
the same type.
3. Secure the battery compartment before use.
Do not dispose of used batteries or rechargeable batteries in house-
hold waste.
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